Electroluminescent lamp panels are well known in the art and comprise a base electrode spaced from a transparent electrode with a phosphorescent layer and a dielectric layer between the two electrodes. Conductive leads extend from the base and transparent electrodes for connection to an AC power source. Current induced between the base and transparent electrodes upon actuation causes the phosphorescent layer to emit light, a phenomenon known as luminescence, that is visible through the transparent electrode, and an electroluminescent lamp can be thought of as a light emitting capacitor. An electroluminescent lamp panel can include one or a plurality of individual electroluminescent lamps.
Two types of electroluminescent lamp panels are in general use, "foil" and "printed", Which terms refer to the nature of the base or non-transparent electrode. The base electrode in a "foil" electroluminescent lamp is a thin aluminum foil layer, whereas the base electrode in a "printed" electroluminescent lamp is a layer printed with conductive ink such as a silver conductive ink.
Electroluminescent lamp panels find substantial use with various types of equipment for which it is desired to provide one or more lighted areas such as for lighting a key pad or control panel. For example, key areas or graphic displays and the like of a membrane switch panel associated with a particular apparatus can be lit with one or more electroluminescent lamps.